Material specification page for parallel dowel pins, unhardened in A4 Stainless Steel. Covers the grade designation (ISO 3506 group A4 (316 / 1.4401), commonly supplied A4-80), corrosion and magnetic behavior, comparable grades and their trade-offs, and the sizes available to ISO 2338.
Why Choose A4 Stainless Steel for Parallel Dowel Pins, Unhardened
Specified for marine, coastal and chemical applications. For parallel dowel pins, unhardened, this matters when superior, including marine and chloride environments is the primary requirement.
Mechanical & Physical Properties
| Grade designation | ISO 3506 group A4 (316 / 1.4401), commonly supplied A4-80 |
|---|---|
| Magnetic response | Largely non-magnetic |
| Service temperature | approx. -200 °C to +400 °C, subject to the property class and the joint |
| Corrosion characteristic | Superior, including marine and chloride environments |
Corrosion Behavior in Service
A4 (316) adds 2–3% molybdenum to the A2 (304) composition, which dramatically improves resistance to chloride-pitting corrosion. For Parallel Dowel Pins, Unhardened in marine, coastal, swimming-pool or food-processing environments, A4 is the default selection.
Comparable Grades
For Parallel Dowel Pins, Unhardened, the alternative stainless grade is A2 (304). The practical dividing line is chlorides: A2 (304) is fine until salt is involved, and A4 (316) exists for the cases where it is — coastal, marine and road-salt service. Neither reaches the strength of a plated class 8.8 or 10.9 fastener.
Using Stainless Fasteners in Aluminum
Stainless steel is more noble than aluminum, so with an electrolyte present — rain, condensation, salt spray — the aluminum becomes the anode and corrodes at the joint. Area ratio decides how bad it gets: a small stainless fastener in a large aluminum section is normally acceptable, a large stainless fastener in thin aluminum is not. Where the joint gets wet, isolate the metals with a coated or nylon washer and a sealant, or specify an aluminum or coated fastener instead.
Sizes of Parallel Dowel Pins, Unhardened Available in A4 Stainless Steel
| Nominal diameter d (mm) | d (mm) | c (mm) | Length range l (mm) | Reference standard |
|---|---|---|---|---|
| 0.6 mm | 0.6 | 0.12 | 2~6 | ISO 2338 |
| 0.8 mm | 0.8 | 0.16 | 2~8 | ISO 2338 |
| 1 mm | 1 | 0.2 | 4~10 | ISO 2338 |
| 1.2 mm | 1.2 | 0.25 | 4~12 | ISO 2338 |
| 1.5 mm | 1.5 | 0.3 | 4~16 | ISO 2338 |
| 2 mm | 2 | 0.35 | 6~20 | ISO 2338 |
| 2.5 mm | 2.5 | 0.4 | 6~24 | ISO 2338 |
| 3 mm | 3 | 0.5 | 8~30 | ISO 2338 |
| 4 mm | 4 | 0.63 | 8~40 | ISO 2338 |
| 5 mm | 5 | 0.8 | 10~50 | ISO 2338 |
| 6 mm | 6 | 1.2 | 12~60 | ISO 2338 |
| 8 mm | 8 | 1.6 | 14~80 | ISO 2338 |
| 10 mm | 10 | 2 | 18~95 | ISO 2338 |
| 12 mm | 12 | 2.5 | 22~140 | ISO 2338 |
| 16 mm | 16 | 3 | 26~180 | ISO 2338 |
| 20 mm | 20 | 3.5 | 35~200 | ISO 2338 |
| 25 mm | 25 | 4 | 50~200 | ISO 2338 |
| 30 mm | 30 | 5 | 60~200 | ISO 2338 |
| 40 mm | 40 | 6.3 | 80~200 | ISO 2338 |
| 50 mm | 50 | 8 | 95~200 | ISO 2338 |
Dimensions are independent of the material: every size above is available in A4 Stainless Steel.
Custom manufacturing · Made to drawing
Need this pin in a grade that is not listed?
A4 Stainless Steel is one of the grades the catalog describes. Tolerance class is what a special pin usually turns on — a locating pin and a retaining pin want very different fits in the same nominal size. Made by cold heading or turning.
Minimum order from 2,000 pieces; samples within 7 days of drawing approval.
